Spectroscopy of Exotic Hadrons Formed from Dynamical Diquarks

Abstract

The dynamical diquark picture asserts that exotic hadrons can be formed from widely separated colored diquark or triquark components. We use the Born-Oppenheimer (BO) approximation to study the spectrum of states thus constructed, both in the basis of diquark spins and in the basis of heavy quark-antiquark spins. We develop a compact notation for naming these states, and use the results of lattice simulations for hybrid mesons to predict the lowest expected BO potentials for both tetraquarks and pentaquarks. We then compare to the set of exotic candidates with experimentally determined quantum numbers, and find that all of them can be accommodated. Once decay modes are also considered, one can develop selection rules of both exact ($J^{PC}$ conservation) and approximate (within the context of the BO approximation) types and test their effectiveness. We find that the most appealing way to satisfy both sets of selection rules requires including additional low-lying BO potentials, a hypothesis that can be checked on the lattice.

14 pages. Version accepted for publication in Phys. Rev D. Includes a new section discussing alternate multiquark approaches

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Cited by in corpus (19)

• The Simple Spectrum of $c\bar{c}c\bar{c}$ States in the Dynamical Diquark Model
• On the mechanism of $T_{4c}(6900)$ tetraquark production
• The Dynamical Diquark Model: First Numerical Results
• Hidden charm tetraquark states in a diquark model
• Spectrum of the Hidden-Bottom and the Hidden-Charm/Strange Exotics in the Dynamical Diquark Model
• Hidden charm pentaquark states in a diquark model
• Tetraquarks in large-$N_c$ QCD
• Fine Structure of Pentaquark Multiplets in the Dynamical Diquark Model
• The Spectrum of $P$-Wave Hidden-Charm Exotic Mesons in the Diquark Model
• Masses of fully-heavy tetraquark states from a four-quark static potential model
• The interplay between compact and molecular structures in tetraquarks
• Production of $Z_{cs}$ in $B$ and $B_s$ decay
• Doubly-Charged $T_{cc}^{++}$ States in the Dynamical Diquark Model
• Exotic Hadrons from Scattering in the Diabatic Dynamical Diquark Model
• Substructure of Multiquark Hadrons (Snowmass 2021 White Paper)
• Doubly charmed hexaquarks in the diquark picture
• Radiative Transitions of Charmoniumlike Exotics in the Dynamical Diquark Model
• Spectrum of Hidden-Charm, Open-Strange Exotics in the Dynamical Diquark Model
• All Heavy Tetraquarks: The Dynamical Diquark Model and Other Approaches